#!/bin/sh

###############################################################################
##
##  HIGH VERBOSITY EXAMPLE
##
###############################################################################

# run from directory where this script is
cd `echo $0 | sed 's/\(.*\)\/.*/\1/'` # extract pathname
EXAMPLE_DIR=`pwd`

# check whether echo has the -e option
if test "`echo -e`" = "-e" ; then ECHO=echo ; else ECHO="echo -e" ; fi

$ECHO
$ECHO "$EXAMPLE_DIR : starting"
$ECHO
$ECHO "This example shows how to use pmw.x to generate better projectors for
$ECHO  LDA+U calculation on FeO. Read file README for more details"

# set the needed environment variables
. ../../../environment_variables

# required executables and pseudopotentials
BIN_LIST="pw.x pmw.x projwfc.x bands.x plotband.x"
PSEUDO_LIST="O.pz-rrkjus.UPF Fe.pz-nd-rrkjus.UPF"

$ECHO
$ECHO "  executables directory: $BIN_DIR"
$ECHO "  pseudo directory:      $PSEUDO_DIR"
$ECHO "  temporary directory:   $TMP_DIR"
$ECHO "  checking that needed directories and files exist...\c"

# check for directories
for DIR in "$BIN_DIR" "$PSEUDO_DIR" ; do
    if test ! -d $DIR ; then
        $ECHO
        $ECHO "ERROR: $DIR not existent or not a directory"
        $ECHO "Aborting"
        exit 1
    fi
done
for DIR in "$TMP_DIR" "$EXAMPLE_DIR/results" ; do
    if test ! -d $DIR ; then
        mkdir $DIR
    fi
done
cd $EXAMPLE_DIR/results

# check for executables
for FILE in $BIN_LIST ; do
    if test ! -x $BIN_DIR/$FILE ; then
        $ECHO
        $ECHO "ERROR: $BIN_DIR/$FILE not existent or not executable"
        $ECHO "Aborting"
        exit 1
    fi
done

# check for pseudopotentials
for FILE in $PSEUDO_LIST ; do
    if test ! -r $PSEUDO_DIR/$FILE ; then
       $ECHO
       $ECHO "Downloading $FILE to $PSEUDO_DIR...\c"
            $WGET $PSEUDO_DIR/$FILE $NETWORK_PSEUDO/$FILE 2> /dev/null
    fi
    if test $? != 0; then
        $ECHO
        $ECHO "ERROR: $PSEUDO_DIR/$FILE not existent or not readable"
        $ECHO "Aborting"
        exit 1
    fi
done

# how to run executables
PW_COMMAND="$PARA_PREFIX $BIN_DIR/pw.x $PARA_POSTFIX"
PROJWFC_COMMAND="$PARA_PREFIX $BIN_DIR/projwfc.x $PARA_POSTFIX"
BANDS_COMMAND="$PARA_PREFIX $BIN_DIR/bands.x $PARA_POSTFIX"
PLOTBAND_COMMAND="$BIN_DIR/plotband.x"
PMW_COMMAND="$PARA_PREFIX $BIN_DIR/pmw.x $PARA_POSTFIX"
$ECHO
$ECHO "  running pw.x as: $PW_COMMAND"
$ECHO "  running pmw.x as: $PMW_COMMAND"
$ECHO "  running projwfc.x as: $PROJWFC_COMMAND"
$ECHO "  running bands.x as: $BANDS_COMMAND"
$ECHO "  running plotband.x as: $PLOTBAND_COMMAND"
$ECHO

# self-consistent calculation with standard LDA
cat > feo_LDA.in << EOF
FeO Wustite in LDA
 &control
    calculation = 'scf'
    restart_mode='from_scratch',
    prefix='feo_af',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
    tprnfor = .true., tstress=.true.
 /
 &system
    ibrav=  0, celldm(1)=8.19, nat=  4, ntyp= 3,
    ecutwfc = 30.0, ecutrho = 240.0, nbnd=20,
    starting_magnetization(1)= 0.0,
    starting_magnetization(2)= 0.5,
    starting_magnetization(3)=-0.5,
    occupations='smearing', smearing='gauss', degauss=0.01,
    nspin=2,
    lda_plus_u=.true.  Hubbard_U(2)=1.d-8, Hubbard_U(3)=1.d-8,
 /
 &electrons
    mixing_mode = 'plain'
    mixing_beta = 0.3
    conv_thr =  1.0d-6
    mixing_fixed_ns = 0
 /
CELL_PARAMETERS
0.50 0.50 1.00
0.50 1.00 0.50
1.00 0.50 0.50
ATOMIC_SPECIES
 O1   1.  O.pz-rrkjus.UPF
 Fe1  1.  Fe.pz-nd-rrkjus.UPF
 Fe2  1.  Fe.pz-nd-rrkjus.UPF
ATOMIC_POSITIONS {crystal}
 O1  0.25 0.25 0.25
 O1  0.75 0.75 0.75
 Fe1 0.0  0.0  0.0
 Fe2 0.5  0.5  0.5
K_POINTS {automatic}
2 2 2 0 0 0
EOF
$ECHO "  1) running scf for FeO in LDA ...\c"
$PW_COMMAND < feo_LDA.in > feo_LDA.out
check_failure $?
$ECHO " done"

# non-self-consistent LDA calculation for band structure plot
cat > feo_nscf.in << EOF
FeO Wustite in LDA
 &control
    calculation = 'bands'
    restart_mode='from_scratch',
    prefix='feo_af-bands',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
    tprnfor = .true., tstress=.true.
 /
 &system
    ibrav=  0, celldm(1)=8.19, nat=  4, ntyp= 3,
    ecutwfc = 30.0, ecutrho = 240.0, nbnd=25,
    starting_magnetization(1)= 0.0,
    starting_magnetization(2)= 0.5,
    starting_magnetization(3)=-0.5,
    occupations='smearing', smearing='gauss', degauss=0.01,
    nspin=2,
    lda_plus_u=.true.  Hubbard_U(2)=1.d-8, Hubbard_U(3)=1.d-8,
 /
 &electrons
    mixing_mode = 'plain'
    mixing_beta = 0.3
    conv_thr =  1.0d-6
    mixing_fixed_ns = 0
 /
CELL_PARAMETERS
0.50 0.50 1.00
0.50 1.00 0.50
1.00 0.50 0.50
ATOMIC_SPECIES
 O1   1.  O.pz-rrkjus.UPF
 Fe1  1.  Fe.pz-nd-rrkjus.UPF
 Fe2  1.  Fe.pz-nd-rrkjus.UPF
ATOMIC_POSITIONS {crystal}
 O1  0.25 0.25 0.25
 O1  0.75 0.75 0.75
 Fe1 0.0  0.0  0.0
 Fe2 0.5  0.5  0.5
K_POINTS {crystal_b}
6
 0.00      0.00     0.00      15  !G
 0.00      0.50     0.00       6  !L
 0.34375   0.8125   0.34375   14  !K'
 0.50      0.50     0.50       8  !T
 0.00      0.00     0.00      16  !G
 0.00      0.50     0.50       0  !X
EOF
# copy restart directory from SCF run
test -d $TMP_DIR/feo_af-bands.save && rm -r $TMP_DIR/feo_af-bands.save
cp -r $TMP_DIR/feo_af.save $TMP_DIR/feo_af-bands.save
cp -f $TMP_DIR/feo_af.occup $TMP_DIR/feo_af-bands.occup
#
$ECHO "  2) running nscf for FeO band structure ...\c"
$PW_COMMAND < feo_nscf.in > feo_nscf.out
check_failure $?
$ECHO " done"

# symmetry analysis of LDA bands
cat > feo_bands.in << EOF
 &bands
    prefix = 'feo_af-bands',
    outdir = '$TMP_DIR/',
    lsym = .TRUE.,
    filband = 'feo_af-bands.dat',
    spin_component = 1,
 /
EOF
$ECHO "  3) performing symmetry analisys of bands ...\c"
$BANDS_COMMAND < feo_bands.in > feo_bands.out
check_failure $?
$ECHO " done"

# projection onto atomic wave functions
cat > feo_proj.in << EOF
 &projwfc
    prefix = 'feo_af-bands',
    outdir = '$TMP_DIR/',
    lsym = .FALSE.,
    filproj = 'feo_af-proj.dat'
 /
EOF
$ECHO "  4) computing atomic projections of bands ...\c"
$PROJWFC_COMMAND < feo_proj.in > feo_proj.out
check_failure $?
$ECHO " done"

# plotband run using the projection weights from .proj to obtain "fat-bands"
# automatically extract Fermi energy from SCF calculation
eFermi=`grep Fermi feo_LDA.out | awk '{print $5}'`
# make a link to the projection file using the name expected by plotband.x
ln -s feo_af-proj.dat.up feo_af-bands.dat.proj
# if feo_af-bands.dat.proj is found, one must supply an additional line with
# the list of atomic wavefunctions (here, the 3d of both Fe ions)
cat > feo_plot.in << EOF
feo_af-bands.dat
  10 11 12 13 14  16 17 18 19 20
 -11.0  25.0
feo_af.bands
feo_af.bands.ps
 $eFermi
 2.0  $eFermi
EOF
$ECHO "  5) using plotband to obtain fat bands for Fe 3d states ...\c"
$PLOTBAND_COMMAND < feo_plot.in > feo_plot.out
check_failure $?
$ECHO " done"
# merging all bands.?.? files produced by plotband in a single file,
# but separated by double blank lines (Gnuplot record style): in this
# way the can be plotted by Gnuplot with one single command
$ECHO "# Merging feo_af.bands.[0-9].[0-9] files as gnuplot records" > feo_af.bands.all
for filgnu in feo_af.bands.[0-9].[0-9];
do
    cat $filgnu >> feo_af.bands.all
    $ECHO "\n" >> feo_af.bands.all
done
## remove all those files?
#rm feo_af.bands.[0-9].[0-9]
# Gnuplot script to plot weighted-bands colored according to the weight
cat > plot.gnu << EOF
#!/usr/bin/gnuplot

set xrange [0.0:3.1868]
unset xtics
set yrange [-21.0:15.0]
set ylabel 'E - E_F  (eV)'

set border lw 2
set style arrow 1 nohead front lw 2 lc rgb 'black'
set label 'G' at graph 0,graph -0.03 center
set arrow from 0.8292,graph 0 to 0.8292,graph 1 as 1
set label 'L' at 0.8292, graph -0.03 center
set arrow from 1.1223,graph 0 to 1.1223,graph 1 as 1
set label "K'" at 1.1223,graph -0.03 center
set arrow from 1.8878,graph 0 to 1.8878,graph 1 as 1
set label 'T' at 1.8878, graph -0.03 center
set arrow from 2.3208,graph 0 to 2.3208,graph 1 as 1
set label 'G' at 2.3208, graph -0.03 center
set label 'X' at graph 1,graph -0.03 center

plot 'feo_af.bands.all' u 1:(\$2 - $eFermi):3 w l palette lw 2 notitle, \\
     0.0 lt 1 lw 2 lc rgb 'grey50' notitle

EOF

# build projected-Wannier functions for Fe 3d states
$ECHO "  6) running poormanwannier post-processing to build Wannier projectors ...\c"
cat > pmw.in << EOF
 &inputpp
    outdir='$TMP_DIR/',
    prefix='feo_af',
    first_band=9, last_band=20,
 /
EOF
$PMW_COMMAND < pmw.in > pmw.out
check_failure $?
$ECHO " done"

# self-consistent calculation with user defined ns + Wannier
cat > feo_wannier.in << EOF
FeO Wustite whithin LDA+U with user defined ns + Wannier
 &control
    calculation = 'scf'
    restart_mode='from_scratch',
    prefix='feo_af',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir='$TMP_DIR/'
 /
 &system
    ibrav=  0, celldm(1)=8.19, nat=  4, ntyp= 3,
    ecutwfc = 30.0, ecutrho = 240.0, nbnd=20,
    starting_magnetization(1)= 0.0,
    starting_magnetization(2)= 0.5,
    starting_magnetization(3)=-0.5,
    occupations='smearing', smearing='gauss', degauss=0.01,
    nspin=2,
    lda_plus_u=.true., Hubbard_U(2)=4.3, Hubbard_U(3)=4.3,
    U_projection_type='file'
    starting_ns_eigenvalue(3,2,2) = 1.d0
    starting_ns_eigenvalue(3,1,3) = 1.d0
 /
 &electrons
    mixing_mode = 'plain'
    mixing_beta = 0.3
    conv_thr =  1.0d-6
    mixing_fixed_ns = 0
 /
CELL_PARAMETERS
0.50 0.50 1.00
0.50 1.00 0.50
1.00 0.50 0.50
ATOMIC_SPECIES
 O1   1.  O.pz-rrkjus.UPF
 Fe1  1.  Fe.pz-nd-rrkjus.UPF
 Fe2  1.  Fe.pz-nd-rrkjus.UPF
ATOMIC_POSITIONS {crystal}
 O1  0.25 0.25 0.25
 O1  0.75 0.75 0.75
 Fe1 0.0  0.0  0.0
 Fe2 0.5  0.5  0.5
K_POINTS {automatic}
2 2 2 0 0 0
EOF
$ECHO "  7) running scf for FeO in LDA+U using Wannier projectors...\c"
$PW_COMMAND < feo_wannier.in > feo_wannier.out
check_failure $?
$ECHO " done"

$ECHO "  cleaning $TMP_DIR...\c"
rm -rf $TMP_DIR/feo_af.*

$ECHO
$ECHO "$EXAMPLE_DIR : done"
